Actress Portia De Rossi has paid tribute to a murdered teenager in a new public service television advert broadcast in America.

Lawrence King, who was reportedly openly gay and sometimes wore ‘feminine’ clothing to school, was shot twice in the head while in class at the E.O. Green School in Oxnard, California last month.

The 60 second commercial, also featuring Grey’s Anatomy star TR Knight, Janet Jackson, Andre 3000 and Ashanti, debuted on America’s gay TV network Logo last week.

During the advert, Rossi comments: “Imagine if wearing make-up and a dress could get you killed.

“For 15-year old Lawrence King, that’s just what happened.”

The actress’s tribute comes after her partner Ellen DeGeneres broke down over the incident on her daytime talk show last month.

The comedienne was close to tears as she told viewers about the case, admitting that she had been deeply affected by the teenager’s murder.

During the emotional speech, the actress said:

“Larry was not a second class citizen and I am not a second class citizen. It’s OK to be gay.”

King was declared brain dead on February 13th as a result of the shooting.

He was taken off life support at St John’s Regional Medical Centre on February 14th and died shortly afterward.

A fourteen-year-old boy, Brandon McInerney, has been charged with first-degree murder and a hate crime in the shooting.

He could face up to 24 years to life for the murder charge and an added three years for the hate crime addition.

According to the Los Angeles Times, McInerney and a gang of boys had recently been taunting King about his sexual orientation.

“This incident is another heartbreaking reminder of how often young people must endure intimidation or violence in school because of their sexual orientation or the way they express their gender identity,” said Joe Solmonese, president of the Human Rights Campaign.

“While California’s residents are fortunate to have state laws that provide some protection against hate crimes and school bullying, this pattern of violence against gay, lesbian, bisexual and transgender students is repeated too often in schools and communities across America each day.”

Scroll down to watch the advert.